Table 6. Leisure time physical activity and multivariable hazard ratio of mortality and years of life gained after age 40 according to smoking and co-morbidity status.
| Variable | Physical Activity Level (MET-h/wk) | |||||
| 0 | 0.1–3.74 | 3.75–7.4 | 7.5–14.9 | 15.0–22.4 | 22.5+ | |
| Smoking status | ||||||
| Never smoker | ||||||
| Number of deaths | 2,521 | 5,430 | 1,814 | 5,857 | 3,200 | 4,283 |
| Multivariable HR | 1.0 | 0.80 | 0.75 | 0.67 | 0.64 | 0.62 |
| 95% CI | Ref | 0.76, 0.84 | 0.70, 0.79 | 0.63, 0.70 | 0.61, 0.68 | 0.59, 0.65 |
| Years of life gained | — | 1.6 | 2.2 | 3.0 | 3.2 | 3.3 |
| 95% CI | Ref | 1.2, 1.9 | 1.6, 2.8 | 2.7, 3.3 | 2.8, 3.6 | 3.0, 3.7 |
| Former smoker | ||||||
| Number of deaths | 4,876 | 9,306 | 3,617 | 10,962 | 6,465 | 8,107 |
| Multivariable HR | 1.0 | 0.77 | 0.72 | 0.63 | 0.55 | 0.52 |
| 95% CI | Ref | 0.74, 0.80 | 0.69, 0.75 | 0.61, 0.65 | 0.53, 0.57 | 0.50, 0.54 |
| Years of life gained | — | 2.2 | 2.8 | 4.1 | 5.0 | 5.5 |
| 95% CI | Ref | 2.0, 2.5 | 2.3, 3.3 | 3.8, 4.3 | 4.8, 5.2 | 5.2, 5.7 |
| Current smoker | ||||||
| Number of deaths | 2,187 | 3,279 | 1,335 | 3,187 | 1,846 | 2,403 |
| Multivariable HR | 1.0 | 0.86 | 0.76 | 0.75 | 0.67 | 0.68 |
| 95% CI | Ref | 0.82, 0.91 | 0.70, 0.81 | 0.71, 0.79 | 0.62, 0.71 | 0.64, 0.72 |
| Years of life gained | — | 1.3 | 2.5 | 2.6 | 3.7 | 3.5 |
| 95% CI | Ref | 0.9, 1.7 | 1.9, 3.1 | 2.1, 3.0 | 3.2, 4.2 | 3.0, 3.9 |
| Pre-existing co-morbidity a | ||||||
| Cancer | ||||||
| Number of deaths | 1,765 | 3,324 | 963 | 3,268 | 1,603 | 2,217 |
| Multivariable HR | 1.0 | 0.81 | 0.74 | 0.65 | 0.59 | 0.55 |
| 95% CI | Ref | 0.76, 0.86 | 0.68, 0.80 | 0.62, 0.69 | 0.55, 0.63 | 0.52, 0.59 |
| Years of life gained | — | 2.7 | 3.6 | 5.3 | 6.2 | 7.0 |
| 95% CI | Ref | 2.2, 3.2 | 2.7, 4.4 | 4.9, 5.7 | 5.7, 6.7 | 6.5, 7.5 |
| Heart disease | ||||||
| Number of deaths | 1,884 | 3,521 | 1,531 | 4,125 | 2,550 | 2,929 |
| Multivariable HR | 1.0 | 0.79 | 0.72 | 0.61 | 0.51 | 0.51 |
| 95% CI | Ref | 0.74, 0.83 | 0.67, 0.77 | 0.58, 0.65 | 0.48, 0.54 | 0.48, 0.54 |
| Years of life gained | — | 2.0 | 2.8 | 4.3 | 5.9 | 6.2 |
| 95% CI | Ref | 1.5, 2.5 | 2.3, 3.4 | 3.9, 4.7 | 5.4, 6.4 | 5.7, 6.7 |
| None | ||||||
| Number of deaths | 6,451 | 12,029 | 4,668 | 13,584 | 7,961 | 10,380 |
| Multivariable HR | 1.0 | 0.80 | 0.75 | 0.68 | 0.63 | 0.61 |
| 95% CI | Ref | 0.78, 0.83 | 0.72, 0.78 | 0.66, 0.70 | 0.60, 0.65 | 0.59, 0.62 |
| Years of life gained | — | 1.6 | 2.0 | 2.8 | 3.4 | 3.7 |
| 95% CI | Ref | 1.4, 1.8 | 1.8, 2.3 | 2.5, 3.0 | 3.2, 3.7 | 3.5, 3.9 |
| Healthy never smokers b | ||||||
| Number of deaths | 1,762 | 3,796 | 1,312 | 4,118 | 2,272 | 3,104 |
| Multivariable HR | 1.0 | 0.79 | 0.75 | 0.68 | 0.67 | 0.65 |
| 95% CI | Ref | 0.75, 0.84 | 0.70, 0.91 | 0.64, 0.72 | 0.62, 0.71 | 0.61, 0.69 |
| Years of life gained | — | 1.4 | 1.8 | 2.6 | 2.7 | 2.8 |
| 95% CI | Ref | 0.9, 1.9 | 1.3, 2.3 | 2.2, 3.0 | 2.2, 3.2 | 2.3, 3.3 |
HRs were calculated in models stratified by study that used age as the underlying time scale. Multivariable models were adjusted for gender, alcohol consumption (0, 0.1–14.9, 15.0–29.9, 30.0+ g/d), education (did not complete high school, completed high school, post-high-school training, some college, completed college), marital status (married, divorced, widowed, unmarried), history of heart disease, history of cancer, BMI (<18.5, 18.5–19.9, 20–22.4, 22.5–24.9, 25–27.4, 27.5–29.9, 30+ kg/m2), and smoking status (never, former, current). If a covariate was a stratification variable for a particular model, then it was excluded from multivariable adjustment. Years of life expectancy gained after age 40 were derived using direct adjusted survival curves [31],[32] for participants who were 40+ y of age at baseline (97.5% of participants).
Years of life expectancy gained after age 60. Cancer and/or heart disease were uncommon prior to this age in our dataset.
Participants who had never smoked and who had no history of heart disease or cancer.